The invention relates to rendering intent selection for document image processing. It finds particular application in conjunction with rendering intent selection based on input color space and will be described with particular reference thereto. However, it is to be appreciated that the invention is also amenable to other applications.
As users of color products become more and more skilled, requirements for control over the image path in a digital front end (DFE) of a image processing system become more pronounced. One example of this is rendering intent selection during image processing of a document image to be rendered. For example, DocuSP 3.0, the Xerox Common Controller/DFE, currently selects rendering intent for document images based on object type.
Rendering intents are simply methods (i.e., sets of rules) for converting colors from one color space to another. They are a standard part of the ICC (International Color Consortium) profile format commonly used in existing color-management systems.
The ICC profile specification defines various rendering intents, including: 1) absolute colorimetric rendering, 2) relative colorimetric rendering, 3) perceptual rendering, and 4) saturation rendering. The rendering intent being used during image processing of a document image defines how colors are mapped from the input color space to the output color space.
Typically, graphics data is processed through the saturation rendering intent to produce vivid output, while images are processed through the perceptual rendering intent to produce true to life pictorials. Such system-specified defaults are available in image processing systems so that users do not need to specify the rendering intent for the document image or for each object type.
Where current mechanisms in color image processing select default rendering intents based on object type, an RGB graphic and a CMYK graphic are rendered through the same rendering intent. This may not always be desirable from the customer perspective.